I say Cap. Utility belt really isn't a deciding factor as Cap has fought both heroes and vilains with various clever weapons and paraphanallea who routinely fight dirty. His mind is enhanced by the serum as well as his body, so Physically, he outclasses Batman and strategically, Bats himself opted for Cap to lead the combined justice league and avengers team for the Marvel/DC- Avengers/JLA crossover (in continuity) stating, 'he's the best man for the job'.
Cap would have the best probability of winning. But it would truly be an epic battle.

__________________"On Olympus, we measure wisdom against Athena...speed against Hermes...power against Zeus. But we measure courage...against Captain America."